In the present study, the effect of glucosamine administration (1.5 or 3 g/day) on cartilage and bone metabolism was investigated in bicycle racers, using cartilage‑ and bone‑specific biomarkers, including C‑terminal cross‑linked telopeptides of type II collagen (CTX‑II), C‑terminal propeptides of type II procollagen (CPII), N‑terminal telopeptide...

This work describes an approach to monitor chondrogenesis of stage-24 chick limb mesodermal cells in vitro by analyzing the onset of type II collagen synthesis with carboxymethyl-cellulose chromatography, immunofluorescence, and radioimmunoassay. This procedure allowed specific and quantitative determination of chondrocytes in the presence of fibroblasts and myoblasts, both of which synthesize ...

The tissue distribution of type II and type IX collagen in 17-d-old chicken embryo was studied by immunofluorescence using polyclonal antibodies against type II collagen and a peptic fragment of type IX collagen (HMW), respectively. Both proteins were found only in cartilage where they were co-distributed. They occurred uniformly throughout the extracellular matrix, i.e., without distinction be...

INTRODUCTION The urinary level of the type II collagen degradation marker CTX-II is increased in postmenopausal women and in ovariectomised rats, suggesting that oestrogen deprivation induces cartilage breakdown. Here we investigate whether this response to oestrogen is also true for other type II collagen turnover markers known to be affected in osteoarthritis, and whether it relates to its pr...

Type IX collagen functions in covalent cross-linkage to type II collagen in cartilage (Eyre, D. R., Apone, S., Wu, J. J., Ericsson, L. H., and Walsh, K. A. (1987) FEBS Lett. 220, 337-341). To understand this molecular relationship better, an analysis of all cross-linking sites labeled by [3H]borohydride was undertaken using the protein prepared from fetal bovine cartilage. Sequence analysis of ...

Skeletal dysplasias represent in vivo models of genetic defects. Achondrogenesis type II (Langer-Saldino), caused by a genetic defect in the major cartilage matrix protein, collagen type II, is a rare and severe skeletal dysplasia. It comprises a severe derangement of the fetal growth plate cartilage with subsequent ossification defects. In this study, we analyzed the matrix composition and cel...

In the present study, to investigate the effect of glucosamine, a component of glycosaminoglycans with a chondroprotective action, on articular cartilage in athletes, we looked at soccer players, who expose their joints to excessive motion and loading, and compared the levels of biomarkers for type II collagen degradation (CTX-II) and type II collagen synthesis (CPII) between soccer players and...

Cathepsin K (EC 3.4.22.38) is a recently described enzyme that has been shown to cleave type I collagen in its triple helix. The aim of this study was to determine if it also cleaves type II collagen in the triple helix and to identify the helical cleavage site(s) in types I and II collagens. Soluble human and bovine type II collagen, and rat type I collagen, were incubated with cathepsin K bef...